PRODUCTION METHOD OF POSITIVE ELECTRODE ACTIVE MATERIAL FOR LITHIUM ION SECONDARY BATTERY AND HEAT TREATMENT DEVICE

• Main Authors: TOKORO HISATO, NAKAJIMA MOTOE, TAKEUCHI AKIO, TAKANO SHUICHI, GUNJI AKIRA, TOYAMA TATSUYA
• Format: Patent
• Language: English; Japanese
• Published: 20.06.2019
• Subjects: BASIC ELECTRIC ELEMENTS; CHEMISTRY; COMPOUNDS CONTAINING METALS NOT COVERED BY SUBCLASSESC01D OR C01F; ELECTRICITY; INORGANIC CHEMISTRY; METALLURGY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

To provide a production method of a positive electrode active material for a lithium ion secondary battery, which enables the production of a positive electrode active material for a lithium ion secondary battery with a high capacity by keeping down the production cost, and a heat treatment device therefor.SOLUTION: A production method of a positive electrode active material for a lithium ion secondary battery comprises: a mixing step of mixing a lithium carbonate with a compound including a metal element other than Li in the formula (1) below; and a baking step. The baking step is arranged to perform a heat treatment under an atmosphere of 45% or more in oxygen concentration and 0.02% or less in carbon dioxide concentration in a firing furnace 10. In the baking step, gas exhausted from the firing furnace 10 is returned to the firing furnace 10 and recycled. A heat treatment device 1 comprises: the firing furnace 10; means 20 for supplying oxygen; a gas return pipe 230; and means 50 for removing carbon dioxide. LiM1O(1)(where M1 is a metal element other than Li, including at least Ni; -0.1≤a≤0.2 and -0.2≤α≤0.2).SELECTED DRAWING: Figure 2 【課題】製造コストを抑制して容量が高いリチウムイオン二次電池用正極活物質を製造できるリチウムイオン二次電池用正極活物質の製造方法及び熱処理装置を提供する。【解決手段】リチウムイオン二次電池用正極活物質の製造方法は、炭酸リチウムと下記式（１）中のＬｉ以外の金属元素を含む化合物とを混合する混合工程と、焼成工程とを有し、焼成工程は、焼成炉１０において酸素濃度が４５％以上、二酸化炭素濃度が０．０２％以下の雰囲気下で熱処理を行う工程であり、焼成工程において、焼成炉１０から排出されたガスを焼成炉１０に返送して再利用する。熱処理装置１は、焼成炉１０と、酸素供給手段２０と、ガス返送管２３０と、二酸化炭素除去手段５０とを備える。Ｌｉ１＋ａＭ１Ｏ２＋α・・・（１）（但し、Ｍ１は、Ｌｉ以外の金属元素であって少なくともＮｉを含み、−０．１≦ａ≦０．２、−０．２≦α≦０．２、を満たす。）【選択図】図２